Recently, the Ministry of Environment in Korea has declared a “law for preventing light pollution generated by artificial lighting”. This law will be enforced from Feb. 1, 2013. The main contents are to protect national health from abusement of the artificial lighting, to prevent harm affecting an ecosystem, and to manage excessive light and intrusive light by determining an acceptable light radiation standard of building lighting, an electronic sign, and lighting of various infrastructures.
At night, in order to prevent generation of the intrusive light which indicates that beams of light of city infrastructure lighting, building lighting, and electronic signs intrude into surrounding buildings, street lights and other lights should follow a light reflection acceptance standard, and light distribution which indicates directions of light radiation should be adjusted.
The light distribution using a Light Emitting Diode (LED) according to the related art relates to a structure of enlarging light distribution of a lighting module as in Patent Laid-Open Publication No. 10-2011-0108269, or relates to a method of adjusting light distribution using a lens as in Patent Registration No. 10-0961676.
However, the structures for enlarging light distribution of a lighting module have a problem in that light pollution is increased by increasing penetration light according to an increase in a light distribution area thereof. Further, the technologies for adjusting light distribution using a lens have problems in that an optical efficiency may be reduced by use of a lens, a proper lens should be replaced as needed, and a proper lens corresponding to each of the lights should be made.